TY - JOUR
T1 - Thermal tuning of advanced Cu sol-gels for mixed oxidation state Cu/Cu xOy materials
AU - Baghi, Roya
AU - Peterson, Geneva R.
AU - Hope-Weeks, Louisa J.
N1 - Copyright:
Copyright 2013 Elsevier B.V., All rights reserved.
PY - 2013/9/28
Y1 - 2013/9/28
N2 - In this report, we describe new conditions for the formation of copper gels and aerogels via epoxide addition to CuBr2 in dimethylformamide (DMF). These CuBr2-derived sols undergo a rapid gel transition and result in materials that have enhanced mechanical properties when compared with the gels derived from CuCl2. Additionally, upon air-annealing, they convert to nanoscopic CuO at temperatures much lower than the CuCl2 analogues. Moreover, annealing under nitrogen results in copper species with reduced oxidization states including Cu2O and metallic Cu. The ratio of copper oxidation states can be controlled by simple modification of the thermal program used to anneal the materials. The thermal reduction of the copper is attributed to retained DMF ligands in the as-prepared aerogels which was confirmed by FTIR spectroscopy. These aerogel materials were characterized by powder X-ray diffraction (PXRD), physisorption, thermogravimetric analysis (TGA), and temperature programmed reduction (TPR).
AB - In this report, we describe new conditions for the formation of copper gels and aerogels via epoxide addition to CuBr2 in dimethylformamide (DMF). These CuBr2-derived sols undergo a rapid gel transition and result in materials that have enhanced mechanical properties when compared with the gels derived from CuCl2. Additionally, upon air-annealing, they convert to nanoscopic CuO at temperatures much lower than the CuCl2 analogues. Moreover, annealing under nitrogen results in copper species with reduced oxidization states including Cu2O and metallic Cu. The ratio of copper oxidation states can be controlled by simple modification of the thermal program used to anneal the materials. The thermal reduction of the copper is attributed to retained DMF ligands in the as-prepared aerogels which was confirmed by FTIR spectroscopy. These aerogel materials were characterized by powder X-ray diffraction (PXRD), physisorption, thermogravimetric analysis (TGA), and temperature programmed reduction (TPR).
UR - http://www.scopus.com/inward/record.url?scp=84882646281&partnerID=8YFLogxK
U2 - 10.1039/c3ta11957b
DO - 10.1039/c3ta11957b
M3 - Article
AN - SCOPUS:84882646281
VL - 1
SP - 10898
EP - 10902
JO - Journal of Materials Chemistry A
JF - Journal of Materials Chemistry A
SN - 2050-7488
IS - 36
ER -